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The evolutionary history of the symbiotic association between arbuscular mycorrhizal fungi (AMF) and embryophytes dates back to the Devonian period. Previous ecological and physiological studies have described the presence of arbuscules, inter- and intracellular hyphae, vesicles, coils and spores, in liverworts and hornworts, which are considered absent in mosses. This study aimed to report the presence of AMF in a community of bryophytes (mosses and liverworts) from Punta Lara Natural Reserve, Argentina. Senescent and green sections of gametophytes were stained and, following microscopic observation, revealed AMF structures. We found intracellular hyphae, vesicles, spores and sporocarps associated with thallus and rhizoids of mosses and liverworts and senescent moss caulidia. The morphological characterization of spores resulted in the determination of Rhizophagus intraradices and Dominikia aurea. The species D. aurea is reported for the first time for Argentina. Sequencing of the D1 variable domain of the LSUrDNA from AMF spores mixes plus hyphae resulted in high similitude to the Dominikia sequences available from NCBI. This study reported the presence of AMF associated with declining and senescent gametophytes of bryophytes (mosses and liverworts) in a Natural Reserve in Argentina. These findings open up new lines of study, which should further investigate these associations and their diversity, physiology and significance. [ABSTRACT FROM AUTHOR]

The genus Nacobbus, known as the false root-knot nematode, is native to the American continent and comprises polyphagous species adapted to a wide range of climatic conditions. Alone or in combination with other biotic and abiotic factors, Nacobbus spp. can cause significant economic yield losses on main food crops such as potato, sugar beet, tomato, pepper and bean, in South and North America. Although the genus distribution is restricted to the American continent, it has quarantine importance and is subject to international legislation to prevent its spread to other regions, such as the European Union. The management of Nacobbus spp. remains unsatisfactory due to the lack of information related to different aspects of its life cycle, survival stages in the soil and in plant material, a rapid and reliable diagnostic method for its detection and the insufficient source of resistant plant genotypes. Due to the high toxicity of chemical nematicides, the search for alternatives has been intensified. Therefore, this review reports findings on the application of environmentally benign treatments to manage Nacobbus spp. Biological control strategies, such as the use of different organisms (mainly bacteria, fungi and entomopathogenic nematodes) and other eco-compatible approaches (such as metabolites, essential oils, plant extracts, phytohormones and amendments), either alone or as part of a combined control strategy, are discussed. Knowledge of potential sources of resistance for genetic improvement for crops susceptible to Nacobbus spp. are also reported. The sustainable strategies outlined here offer immediate benefits, not only to counter the pathogen, but also as good alternatives to improve crop health and growth. [ABSTRACT FROM AUTHOR]

Copyright of BIOAGRO is the property of Revista BIOAGRO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Polylepis woodlands are one of the most threatened mountain ecosystems of South America, and their restoration is a high priority. To assess the mycorrhizal status in Polylepis woodlands of [...]

Objectives: To know the experiences of Venezuelan migrant women living in shelters in Roraima state at the northwestern border between Venezuela and Brazil regarding situations of violence as part of the dynamics of everyday life. Materials and methods: Data were collected in January 2020 through 12 focus group discussions (FGDs) with 5 to 14 Venezuelan migrant women aged 18–49 years old living transitorily in five shelters established by the United Nations High Commissioner for Refugees (UNHCR) and the Brazilian government. We obtained individual and shared views on the experiences regarding violence that migrant women may experience in their everyday life. To organize the FGDs, variations in age and the time women were living at the shelters were considered. All FGDs were held in a place at the shelter that guaranteed privacy and secrecy so that women could express themselves freely. The initial question was broad and open ended and was followed by more specific questions about situations of domestic violence and other types of violence. Results: The main themes identified were the following: i) women's perceptions on domestic violence, ii) women's perceptions on how humanitarian organizations were managing the episodes of domestic violence, and iii) situations considered violence in everyday life at the shelters. The FGDs showed that the reported violence inside the shelters was high, and several forms of violence emerged. Violence was identified as physical aggression and psychological threats, and violence in everyday life at the shelter included xenophobia when the migrants went outside the shelters that was perceived and described as violence. Conclusions: According to the perspective of Venezuelan migrant women violence was part of everyday life among those living in the UNHCR shelters at the northwestern border of Brazil-Venezuela. These women are not comfortable with this situation, and it is difficult for them to understand and handle the episodes of violence. [ABSTRACT FROM AUTHOR]

The monitoring of infrared thermal images is reported to analyze changes in skin temperature in the hand fingers when repetitive work is performed to know which finger has a greater risk of injury, besides, the recovery time is analyzed regarding the initial temperature and its relationship with age, sex, weight, height if practice sports, and Body Mass Index (BMI) per individual. For the above, an experimental test was carried out for 10 minutes on a repetitive operation that takes place in the telecommunications industry and 39 subjects participated in which an infrared thermal image of the dorsal and palmar part of both hands was taken in periods of 5 minutes after the 10-minute test has elapsed. The results show that none of the participants recovered their initial temperature after 10 minutes of the experimental test. In addition, it was found that there is a relationship between skin temperature and sex, and that age influences the recovery of temperature. On the other hand, the thumb, index, and middle fingers have a higher risk of injury in the analyzed task. It is concluded that performing repetitive work with all the fingers of the hand does not show that all they have the same risk of injury, besides that, not all the variables studied affect the recovery of temperature and its behavior. [ABSTRACT FROM AUTHOR]

Background and aims: Algae and Cyanobacteria species that grow in contaminated sites can accumulate high concentrations of heavy metals. In this work it was proposed to a) characterize the community of algae and Cyanobacteria and b) evaluate the effect of lead (Pb) on the composition of algae present in the rhizosphere of plants capable to accumulate Pb in Córdoba province. M&M: Soil samples were taken from the rhizosphere of Sorghum halepense, Bidens pilosa and Tagetes minuta at sites with different levels of Pb. In the laboratory, the soil was sown in capsules with sterilized Watanabe medium. The cultures grew 9 weeks. The algae and Cyanobacteria were identified over the time and the final relative frequency analyzed. Results: In contaminated soils, 24 species of Cyanobacteria, Chloroplastida and Xanthophyceae were identified. The heterocytous cyanobacteria Cylindrospermum muscicola, Nostoc commune and Calothrix clavata registered a relative mean frequency (between 21 and 60%). Trebouxia parmeliae (Chloroplastida) and Vaucheria sp. (Xanthophyceae) were present in soils with the highest level of Pb. Most of the species were concentrated in the lowest levels of Pb. Conclusions: A negative effect of Pb on the species richness of algae and Cyanobacteria was observed in the rhizosphere of the evaluated plants. Based on the composition of the community of algae and Cyanobacteria in the soil, two groups are determined and could be considered tolerant and non-tolerant communities of Pb contamination. [ABSTRACT FROM AUTHOR]

Objective: We evaluated clinical performance when the TCu380A intrauterine device (IUD) and the levonorgestrel (LNG) 52‐mg intrauterine system (IUS) were inserted by different categories of healthcare professionals. Methods: A retrospective study was conducted at the University of Campinas, Brazil. The medical records were reviewed of all women in whom an IUD was inserted between January 1980 and December 2018, with data for at least 1 year, and for whom information on the healthcare provider who inserted the device was available. Results: Overall, 19 132 (76.9%) IUD and 5733 (23.1%) LNG‐IUS insertions were included, with residents/interns performing 13 853 (55.8%), nurses 7024 (28.2%), and physicians 3988 (16.0%). Removals for pregnancy and infection were significantly higher when physicians inserted the device, while removals for bleeding/pain and other medical reasons were more common when nurses performed the insertion. Expulsion and removals for personal reasons were similar for all three categories. Conclusion: Clinical outcomes were similar regardless of whether trained nurses, residents/interns, or physicians inserted the device, and were irrespective of users' age and parity. These results could stimulate other healthcare services, particularly in regions where there is a shortage of physicians, to invest in training nurses to perform insertions of IUDs. Clinical outcomes were similar regardless of whether trained nurses, residents/interns, or physicians inserted the intrauterine device. [ABSTRACT FROM AUTHOR]

Copyright of Ecologia Austral is the property of Asociacion Argentina de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil erosion affects extensive areas worldwide and must be urgently reduced promoting plant cover and beneficial microorganisms associated with plants, including arbuscular mycorrhizal fungi (AMF). In mountain environments, plant cover is difficult to enhance due to harsh conditions during the dry season and steep slopes. Our objective was to evaluate the percentage of the soil surface covered by plants and the AMF community associated with trees 12.5 years after planting during forest restoration efforts in microsites at different levels of soil degradation. The study was performed in the first montane forest restoration initiative of Central Argentina, where one of the trials consisted of planting Polylepis australis saplings at microsites with different levels of soil degradation: high, intermediate, and low. After 12.5 years, percentage of bare soil cover was significantly reduced by 36 and 37% in the high and intermediate degradation microsites, respectively. Low degradation microsites were initially very low in bare soil and did not significantly change. Mycorrhizal colonization, hyphae, vesicles, arbuscules, AMF diversity, and community structure were similar among microsite types. Percentage of hyphal entry points was higher at microsites with low degradation, number of spores was higher in high and intermediate degradation, and species richness was higher in high degradation. Acaulospora and Glomus were the most abundant genera in all microsites. We conclude that even in the most degraded microsites around 2.8% of the bare soil is covered by vegetation each year and that the arbuscular mycorrhizal community is highly tolerant and adapted to soils with different disturbance types. [ABSTRACT FROM AUTHOR]

Office work involves maintaining fixed postures for long periods, which leads to the development of skeletal muscle disorders, which is why an ergonomic evaluation is necessary to avoid health problems. The objective of this study is to evaluate, by means of ergonomic methods, the risk of postural loading of workers in the loan area of a library, in order to reduce the health problems associated with musculoskeletal disorders in the administrative area; A woman and a man were evaluated and three work cycles were analyzed: loan, refund and fine. The evaluations were with the Rapid Office Strain Assessment (ROSA) y (Rapid Entire Body Assesment (REBA) method respectively, both anthropometric and work area measurements were taken, and improvements. The results obtained through the methods allowed to inquire about the need to carry out improvement actions to address the inadequate postures and the organization of the workspace. Once the recommendations are implemented, favorable results are obtained, the workers' position improves, the risk level of REBA decreases from 9 to 3 for the case of the woman and from 6 to 2 for the case of the man, concluding that the recommendations were favorable to avoid or diminish the Skeletal Muscle Disorders. [ABSTRACT FROM AUTHOR]

Copyright of Boletín de la Sociedad Argentina de Botánica is the property of Sociedad Argentina de Botanica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Arbuscular mycorrhizal fungi (AMF) colonize approximately 82% of land plants in every ecosystem, even in extreme conditions such as saline soils. In the present work we report the arbuscular mycorrhizal colonization and its vertical root concentration in four Chenopodiaceae plants species (Allenrolfea patagonica, Atriplex argentina, Heterostachys ritteriana and Suaeda divaricata) at five different soil depths in two salines of central Argentina. All the plant species showed mycorrhizal colonization and varied significantly among plant species and sites for all soil depths. Atriplex argentina presented the highest mycorrhizal colonization at almost all soil depths (0-50 cm). In all plant species root concentration decrease as depth increases at both sites. The presence of mycorrhizal roots in the deeper layers of soil in the four Chenopodiaceae plants species, shows that these fungi are tolerant to live in the saline soils of central Argentina. [ABSTRACT FROM AUTHOR]

The Yungas, a system of tropical and subtropical montane forests on the eastern slopes of the Andes, are extremely diverse and severely threatened by anthropogenic pressure and climate change. Previous mycological works focused on macrofungi (e.g. agarics, polypores) and mycorrhizae in Alnus acuminata forests, while fungal diversity in other parts of the Yungas has remained mostly unexplored. We carried out Ion Torrent sequencing of ITS2 rDNA from soil samples taken at 24 sites along the entire latitudinal extent of the Yungas in Argentina. The sampled sites represent the three altitudinal forest types: the piedmont (400-700 m a.s.l.), montane (700-1500 m a.s.l.) and montane cloud (1500-3000 m a.s.l.) forests. The deep sequence data presented here (i.e. 4 108 126 quality-filtered sequences) indicate that fungal community composition correlates most strongly with elevation, with many fungi showing preference for a certain altitudinal forest type. For example, ectomycorrhizal and root endophytic fungi were most diverse in the montane cloud forests, particularly at sites dominated by Alnus acuminata, while the diversity values of various saprobic groups were highest at lower elevations. Despite the strong altitudinal community turnover, fungal diversity was comparable across the different zonal forest types. Besides elevation, soil pH, N, P, and organic matter contents correlated with fungal community structure as well, although most of these variables were co-correlated with elevation. Our data provide an unprecedented insight into the high diversity and spatial distribution of fungi in the Yungas forests. [ABSTRACT FROM AUTHOR]

Information about the interaction between arbuscular mycorrhizal fungi (AMF) and the false root-knot nematode Nacobbus aberrans (Thorne, 1935) Thorne & Allen, 1944 is scarce. The effect of Glomus intraradices Schenk & Smith on tomato ( Lycopersicon esculentum L.) cv. Platense inoculated with nematode juveniles from Lisandro Olmos (Argentina) was studied under greenhouse conditions. Six treatments with five replications were performed. After 80 days, nematode reproduction and percentage of AMF colonization in roots were estimated. Some plant growth parameters were also measured. In general, plants with AMF and AMF plus nematodes grew as well as the control without AMF and without nematodes. Furthermore, G. intraradices was beneficial in reducing nematode-induced damage in roots (lower number of galls) as well as in having a suppressive effect on parasite reproduction. This is the first study on the use of G. intraradices as a possible strategy in the control of N. aberrans in tomato. [ABSTRACT FROM AUTHOR]

Abstract: Polylepis australis trees endemic to Argentina dominate the canopy of subtropical high altitude forests. Here, livestock rearing is the main economic activity and is suspect of the low performance of P. australis trees through direct and indirect effects which could include the reduction in arbuscular mycorrhizal fungi (AMF) and their benefit to trees. To elucidate the role of AMF, we compare plant performance indicators, arbuscular mycorrhizal (AM) colonization and AMF communities in 20 trees distributed in two areas of central Argentina which differed in livestock grazing intensity. The area with high livestock density presented more soil degradation and trees with a lower overall plant performance than the area with reduced livestock density. The AM colonization values of P. australis were considerably higher than reported for other tree species and the area with high livestock density had a lower proportion of arbuscules and higher proportion of hyphae, while vesicles and AM colonization – all structure considered together – did not differ between areas. Overall AMF spore number and of most species when considered separately was significantly higher in the area with high livestock density, suggesting a high tolerance and adaptation of AMF to livestock. We conclude that a reduction in livestock improves the performance of P. australis, that this improvement could be mediated by an increase in the proportion of arbuscules, but there does not appear to be any limitation in AM colonization or AMF spore number which could otherwise be limiting forest restoration. [Copyright &y& Elsevier]

In this study we investigated the capacity of Andean alder ( Alnus acuminate Kunth), inoculated with Frankia and two ectomycorrhizal fungi ( Alpova austroalnicola Dominguez and Alpova diplophloeus ([Zeller and Dodge] Trappe and Smith), for nodulation and growth in pots of a soilless medium that contained vermiculite or a mixture of ground basalt rock and vermiculite. The seedlings were inoculated with Frankia suspensions prepared from root nodules of A. Acuminate, followed by inoculation with spores of either one of the two Alpova species. The seedlings were grown in a greenhouse for 12 months. The seedlings grown in the vermiculite-based growth medium containing large (1-3 mm) basalt particles and Alpova austroalnicola or medium-sized (0.5-1 mm) basalt particles and A. Diplophloeus had the heaviest shoot and root nodule dry weights and abundant ectomycorrhizal colonization. Ectomycorrhizas formed by A. Acuminate with Alpova austroalnicola is described here for the first time. Growth of Alnus acuminate inoculated with ectomycorrhizal fungi and Frankia in the soilless primary minerals indicates that Andean alder can alter resource supply by tapping an otherwise unavailable nutrient source. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine patterns of arbuscular mycorrhizal (AM) colonization of Alnus acuminata Kunth at two natural forests in relation to soil parameters at two different seasons (autumn and spring). The soil parameters studied were field capacity, pH, electrical conductivity, available P, total N and Organic matter. The percentage of AM colonization was estimated and correlated to soil properties and to two different seasons. The results indicate that the percentage of AM colonization varied among soil types and was higher in spring than autumn. A significant positive correlation was found between AM colonization and electrical conductivity, organic matter and total Nitrogen. Results of this study provide evidence that AM colonization of A. acuminata can be affected by some soil parameters and seasonality. [ABSTRACT FROM AUTHOR]

Bidens pilosa frequently forms a symbiotic association with arbuscular mycorrhizal fungi (AMF). This plant species can grow in Pb-polluted soils, accumulating Pb in its tissues. The aims of the study were to determine whether Pb accumulated in the tissues of B. pilosa can be transferred to the soil through AMF and to compare the role of AMF communities that have a history of exposure to the contaminant with those that have never been exposed. The experiment combined plants with and without Pb accumulated in their tissues, and inoculated with AMF collected from the rhizosphere of B. pilosa in soils contaminated and not contaminated with Pb. The results showed that AMF participate in the removal of Pb that had entered the plant and release it into the soil, as evidenced by the presence of Pb in the AMF spores and in the glomalin produced by AMF. We propose that Pb accumulation in AMF spores would be a protection mechanism that interrupts Pb uptake by the plant; however, that mechanism would not be fully exploited in detoxification, whereas the production of Pb-enriched glomalin could be an important detoxification mechanism to eliminate Pb already taken up by plants. AMF with a history of Pb exposure achieved only higher rates of root colonization, while AMF without previous exposure showed higher Pb concentration in the spores and higher glomalin production, and successfully removed Pb from both the roots and aboveground parts of the plant. The use of AMF communities not adapted to Pb may be a more effective option for microbe-mediated phytoremediation methods in which detoxification mechanisms are desirable. [Display omitted] • Arbuscular mycorhizal fungi participate in Pb detoxification from plant to soil. • The main mechanism of Pb removal is through glomalin production. • Pb exposure history of AMF may influence Pb detoxification. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) are considered as a possible alternative for the biological control of plant-parasitic nematodes. The false root-knot nematode Nacobbus aberrans is an endoparasite that induces the formation of galls in plant roots and causes severe damage to crops of economic importance. The purpose of the study was to evaluate the effect of the individual and combined application of two AMF species ( Rhizophagus intraradices and Funneliformis mosseae ) on the tomato root penetration of N. aberrans second-stage juveniles (J2). Forty-five days after the application of AMF, 300 J2 were inoculated per plant. Tomato roots were analyzed after 4, 8 and 12 days in order to quantify the nematodes that had invaded them. Plants inoculated with AMF presented a lower number of juveniles within the roots compared with non-mycorrhizal plants. No significant differences were observed between the individual and combined application of AMF regarding the number of nematode juveniles. The use of R. intraradices and F. mosseae (both individually and combined) reduced the entry of nematodes in tomato roots. The antagonistic effect of AMF on the invasion of N. aberrans J2 is reported for the first time. [ABSTRACT FROM AUTHOR]

In this study, the content of Pb, the physico-chemical and biological parameters in soils, and the metal transfer to vegetative and reproductive Sorghum bicolor plants were evaluated along with their relationship with the toxicological risk of crop consumption. To carry this out, soil and sorghum samples at different growth stages were collected near to a former battery recycling plant. The results showed that the concentrations of Pb in soils at several sites were above the maximum permissible levels. Metal bioavailability was not directly related to the pH, OM% or EC, while no association between metals and the different genera of fungi was observed. Sorghum crops accumulated Pb mainly in the roots in all of the growth stages, and therefore presented low levels of Pb in aerial parts without toxicological risk due to direct consumption. Taken together, our results revealed that sorghum could be employed as a potential phytostabilizator of lead in soils associated with crop production. However, further studies are necessary to extend these findings. [ABSTRACT FROM AUTHOR]